1. Field of the Invention
The invention relates to a surface area vacuum gripper for sucking onto and handling workpieces, with a housing, which is provided with a negative pressure chamber that can be acted upon with negative pressure and the housing comprises suction openings on its side facing the workpiece.
2. Description of the Related Art
Surface area vacuum grippers serve in particular for gripping and lifting of objects, such as positionally stable flat materials, such as boards or plates, or smaller objects, such as cans, cups, dishes or the like. The surface area vacuum gripper comprises a flexible lining, which is usually applied to the top side of the objects to be gripped. Foam lining has proven as advantageous, because it conforms well to the sometimes uneven surface. There is, however, still the problem that different objects have different surfaces and sometimes large gaps exist between the objects.
However, the flow behavior of the conventional suction grippers is too slow to quickly respond to different objects.
If the surface area vacuum gripper is equipped with flow valves with a predetermined suction, the valve bodies must not be too sluggish, because otherwise they do not close. Fast-acting valve bodies carry the risk that they will close when a sucked-on workpiece e.g. is briefly lifted by vibration so that briefly ambient air is sucked in. In this case, the workpiece would drop.
Publications U.S. Pat. No. 7,661,736 B2, DE 36 36 523 C2, DE 198 17 217 C1, DE 10 2006 050 970 A1, U.S. Pat. No. 3,910,621 A and EP 0 267 874 A1 describe surface area vacuum grippers, in which components are arranged in the negative pressure chamber.